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  • Heat tolerance, oxidative stress response tuning and robust gene activation in early-stage Drosophila melanogaster embryos
Title: Heat tolerance, oxidative stress response tuning and robust gene activation in early-stage Drosophila melanogaster embryos
In organisms with complex life cycles, life stages that are most susceptible to environmental stress may determine species persistence in the face of climate change. Early embryos ofDrosophila melanogasterare particularly sensitive to acute heat stress, yet tropical embryos have higher heat tolerance than temperate embryos, suggesting adaptive variation in embryonic heat tolerance. We compared transcriptomic responses to heat stress among tropical and temperate embryos to elucidate the gene regulatory basis of divergence in embryonic heat tolerance. The transcriptomes of tropical and temperate embryos differed in both constitutive and heat-stress-induced responses of the expression of relatively few genes, including genes involved in oxidative stress. Most of the transcriptomic response to heat stress was shared among all embryos. Embryos shifted the expression of thousands of genes, including increases in the expression of heat shock genes, suggesting robust zygotic gene activation and demonstrating that, contrary to previous reports, early embryos are not transcriptionally silent. The involvement of oxidative stress genes corroborates recent reports on the critical role of redox homeostasis in coordinating developmental transitions. By characterizing adaptive variation in the transcriptomic basis of embryonic heat tolerance, this study is a novel contribution to the literature on developmental physiology and developmental genetics.  more » « less
Award ID(s):
1750322
PAR ID:
10652885
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
The Royal Society Publishing
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
291
Issue:
2029
ISSN:
0962-8452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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